Posted By Lloyd Alter On October 15, 2009 @ 2:30 pm In Architecture,Green Building | No Comments

Buildings consume 76% of electricity generated; they create 48% of our greenhouse gases; a quarter of our waste[1] in landfills comes from construction. Yet we continue to tear down perfectly good ones and replace them with new ones that don’t perform as well and don’t last as long. If we understood what old buildings[2] are saying to us, we would be less eager to rip them down, and perhaps might even emulate them in our new buildings. Read on for examples.

Photo from Smithsonian

1. Use Natural Ventilation

A hundred years ago, even the crappiest tenement in New York[3] had an air shaft; you were not allowed to build kitchens or bathrooms without windows. There wasn’t much of a view, but the stack effect sucked air through the unit and up the middle. Then mechanical fans were approved, and builders no longer had to pay the price for these. Now if you want ventilation[4], you need electricity.

Photo by Lloyd Alter

You don’t have to go back that far; when I was in Florida in February two years ago I was stayed in the building on the left, a modern center hall design with no cross ventilation. We had to run the air conditioner because there was no air movement at all. Next door, the building the right, had a single loaded open corridor. You could see that all of the residents had transom windows over their doors wide open, and were ventilating their units without air conditioning. More: Big Steps In Building: Make Natural Ventilation Mandatory[5].

2. Design “Tunable” Windows

The windows on your home are not just holes in the wall that you open or close, they are actually part of a sophisticated ventilation machine. People used to take it for granted that you tune them for the best ventilation, but in this thermostat age we seem to have forgotten how.

Photo from White Pine Manual (1918)

If you have double hung windows, you can open the bottom section of the upwind side of the house and the upper section of the downwind side, and the low pressure will suck the air through your house. Make the outlet openings larger than the inlet opening, it increases the draft. That is why I love double hung windows; they offer the most flexibility and options. Put on operating adjustable shutters and you have security and ventilation at the same time, as well as protection in storms. More: Tune Your Windows; They are not just holes in the walls.[6]

Photo by Lloyd Alter

3. Plant A Tree

I have the most amazingly sophisticated air conditioning system. In the summer, it blocks the sun almost completely, keeping my home in shade. Not only that, it pumps water from the ground and evaporates it from leaves, cooling the air around them. Now, in autumn, the leaves are turning colours and falling off; in another few weeks the sun will stream through the branches, filling my windows with warming sunshine. Who could plan it better than that? More: Be Cool and Plant A Tree[7].

Pennsylvania Station in New York

4. Don’t Make Light When You Can Pipe it, Move it, and Bend it

The old Pennsylvania Station in New York not only had an amazing glass roof, but it had a glass floor to let light into the lower train platforms. It was called prism glass. The ceiling might have looked like this[8]. Other buildings used vertical prisms[9] to direct light deep into buildings. Frank Lloyd Wright even got a patent[10] on the stuff. It was everywhere.

Left: Solartube. Right: Parans fiber optic system

Today there are all kinds of ways of piping natural light into your spaces, from the Solatube[11] to the Parans fiber optic[12] system from Sweden. There is also an interesting Australian system, Dayray[13]. Big windows and high ceilings are the easiest way to go, but when you can’t put in a window, pipe it. Natural light[14] changes color over the course of a day and your body clock looks for that, so working under natural light makes the day go faster. Needless to say, it also saves on energy. More: The Suntracker One-Ups the Skylight[15].

Image by Lloyd Alter

5. Make Buildings Look Like Letters Again

Buildings used to look like alphabets, to minimize the distance to an exterior wall and maximize natural light and ventilation. We have all seen many Cs, Os and a few Es (I forgot to draw probably the most common, the Ls).

The engineers would say that the heat loss or gain through so much exterior wall would use far more energy than would be saved using daylight and natural cross-ventilation. They would say that the most efficient building would maximize the floor plate and minimize the perimeter, the size of windows and the amount of air change. That is what they did in the 70’s and how we got a lot of toxic buildings. We can do better. More: Architects: Go Back To The ABCs and Design Buildings Like Letters Again[16].